/* Modern Design System */
:root {
  /* Primary Colors */
  --primary-50: #eff6ff;
  --primary-100: #dbeafe;
  --primary-200: #bfdbfe;
  --primary-300: #93c5fd;
  --primary-400: #60a5fa;
  --primary-500: #3b82f6;
  --primary-600: #2563eb;
  --primary-700: #1d4ed8;
  --primary-800: #1e40af;
  --primary-900: #1e3a8a;

  /* Secondary Colors */
  --secondary-50: #f0f9ff;
  --secondary-100: #e0f2fe;
  --secondary-200: #bae6fd;
  --secondary-300: #7dd3fc;
  --secondary-400: #38bdf8;
  --secondary-500: #0ea5e9;
  --secondary-600: #0284c7;
  --secondary-700: #0369a1;
  --secondary-800: #075985;
  --secondary-900: #0c4a6e;

  /* Accent Colors */
  --accent-50: #fdf4ff;
  --accent-100: #fae8ff;
  --accent-200: #f5d0fe;
  --accent-300: #f0abfc;
  --accent-400: #e879f9;
  --accent-500: #d946ef;
  --accent-600: #c026d3;
  --accent-700: #a21caf;
  --accent-800: #86198f;
  --accent-900: #701a75;

  /* Neutral Colors */
  --neutral-50: #f8fafc;
  --neutral-100: #f1f5f9;
  --neutral-200: #e2e8f0;
  --neutral-300: #cbd5e1;
  --neutral-400: #94a3b8;
  --neutral-500: #64748b;
  --neutral-600: #475569;
  --neutral-700: #334155;
  --neutral-800: #1e293b;
  --neutral-900: #0f172a;

  /* Success Colors */
  --success-50: #f0fdf4;
  --success-100: #dcfce7;
  --success-200: #bbf7d0;
  --success-300: #86efac;
  --success-400: #4ade80;
  --success-500: #22c55e;
  --success-600: #16a34a;
  --success-700: #15803d;
  --success-800: #166534;
  --success-900: #14532d;

  /* Warning Colors */
  --warning-50: #fffbeb;
  --warning-100: #fef3c7;
  --warning-200: #fde68a;
  --warning-300: #fcd34d;
  --warning-400: #fbbf24;
  --warning-500: #f59e0b;
  --warning-600: #d97706;
  --warning-700: #b45309;
  --warning-800: #92400e;
  --warning-900: #78350f;

  /* Error Colors */
  --error-50: #fef2f2;
  --error-100: #fee2e2;
  --error-200: #fecaca;
  --error-300: #fca5a5;
  --error-400: #f87171;
  --error-500: #ef4444;
  --error-600: #dc2626;
  --error-700: #b91c1c;
  --error-800: #991b1b;
  --error-900: #7f1d1d;

  /* Semantic Variables */
  --background: var(--neutral-50);
  --surface: #ffffff;
  --surface-hover: var(--neutral-100);
  --surface-active: var(--neutral-200);
  
  --text-primary: var(--neutral-900);
  --text-secondary: var(--neutral-600);
  --text-muted: var(--neutral-500);
  --text-inverse: #ffffff;
  
  --border: var(--neutral-200);
  --border-hover: var(--neutral-300);
  --border-focus: var(--primary-500);
  
  --primary-color: var(--primary-500);
  --primary-hover: var(--primary-600);
  --primary-light: var(--primary-100);
  
  --success-color: var(--success-500);
  --warning-color: var(--warning-500);
  --error-color: var(--error-500);
  
  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-3xl: 2rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition: var(--transition-normal);
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-background: var(--vt-c-black);
    --color-background-soft: var(--vt-c-black-soft);
    --color-background-mute: var(--vt-c-black-mute);

    --color-border: var(--vt-c-divider-dark-2);
    --color-border-hover: var(--vt-c-divider-dark-1);

    --color-heading: var(--vt-c-text-dark-1);
    --color-text: var(--vt-c-text-dark-2);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  font-weight: normal;
}

body {
  min-height: 100vh;
  color: var(--text-primary);
  background: linear-gradient(135deg, var(--background) 0%, var(--neutral-100) 100%);
  transition: color var(--transition), background-color var(--transition);
  line-height: 1.6;
  font-family: 
    'Inter',
    -apple-system,
    BlinkMacSystemFont,
    'Segoe UI',
    'Roboto',
    'Oxygen',
    'Ubuntu',
    'Cantarell',
    'Fira Sans',
    'Droid Sans',
    'Helvetica Neue',
    sans-serif;
  font-size: 16px;
  font-weight: 400;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.01em;
}

/* Global Styles */
* {
  box-sizing: border-box;
}

*::before,
*::after {
  box-sizing: border-box;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.025em;
  color: var(--text-primary);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Focus Styles */
*:focus {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

*:focus:not(:focus-visible) {
  outline: none;
}

/* Selection */
::selection {
  background-color: var(--primary-100);
  color: var(--primary-900);
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--neutral-100);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
  background: var(--neutral-300);
  border-radius: var(--radius-full);
  transition: background var(--transition);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--neutral-400);
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}
